The Cassinis were important figures in the mapmaking world. Jean Dominique Cassini, originally an Italian astronomer and mathematician, moved to France and was appointed director of Paris Observatory in 1669. He produced a number of maps before his death in 1712. After his death his son, Jacques Cassini de Thury, became director and conducted a major survey known as the Triangulation of France with his own son, César Francois Cassini. This survey led to the famous Carte de Cassini which was finally published in 1789 (Tooley, 107; Moreland and Bannister 124-5).

The land of "Iesso" (a.k.a Jesso, Yezo, Jeco, etc) was an island allegedly lying north of Japan. Later identified as Hokkaido, explorers in the seventeenth century were unsure of its nature. The Russians attempted to discern whether Yezo was indeed an island or part of Asia with a number of expeditions in the seventeenth century. Under the reign of Peter the Great, the explorers were able to chart Russia's Kamchatka Peninsula and the Kurile Islands. In the 1780s, a French expedition sailed between Yezo and Korea, and then, through the Kuriles (Tooley and Bricker, 130).

Anian was another mythical kingdom that appeared on many maps. This area usually appears between North America and Asia as a possible passage. The name originates in Marco Polo's travel reports (Wagner, 426). The Strait of Anian was first recorded in a pamphlet in 1562 by Giacomo Gastaldi. The Strait then appears on a map in 1566, usually at 67 degrees latitude. Wagner writes that the strait usually appeared as a "narrow crooked strait connecting the Pacific Ocean with the Polar Ocean." Over time Anian was used to describe a strait that connected to Hudson's Bay. Other cartographers located the Strait of Anian near Japan where it stood as the strait found by De Vries in 1643 (Wagner, 426). Anian and the associated Strait of Anian eventually became known as the Bering Strait (Hayes 34).

Source(s):

Hayes, Derek. "America Discovered: A Historical Atlas of North American Exploration. Vancouver: Douglas and McIntyre, 2004.